During the first escape attempt in Portal 2 (when GLaDOS is still in charge) she opens a door for you which you can choose to go through instead of following Wheatley (the blue-eyed ball). What happens if you go there?

@Juan Manuel: It's a beautiful day out. Yesterday I saw a deer. If you come back, we can ride an elevator all the way up to the break room, and I'll tell you about the time I saw a deer again.
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BoltClockJun 6 '11 at 15:00

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@TheAnnoyingPyro I didn't see the deer today, but I did see some humans. But with you here I have more test subjects than I'll ever need.
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user56Jun 7 '11 at 20:32